High volume production for structural parts focuses on low cost materials and low assembly costs, but may initially require a long-term investment of high capital for tooling and equipment. However, the high volume production may not adapt to design variations easily.
Presently, low volume production for parts involves low capital expenditures, expensive materials and high assembly costs, for example, aluminum components. Overall, low volume production is still very expensive.
It is desirable to produce light weight, strong, and stiff composites for fabricating a structure component, such as a chassis, panels for communication equipment, frames or body parts for transportation or vehicles (e.g., bicycles, motor cycles, trucks etc.), agricultural applications (e.g., agricultural equipment), energy related applications (e.g., wind power, solar), satellite applications, aerospace applications, construction materials (e.g., building materials and the like), and consumer products (e.g., furniture, toilet seats, and electronic products among others).
It is desirable to produce light weight, strong composite components with good energy absorption for fabricating a chassis or a body component, such as a car hood or other body panel. The body components may be designed to provide energy absorption during a car accident. For safety reasons, the car hood or the body components may be designed to have some damping or energy absorption characteristics.
Composite components for the transportation (e.g., auto, truck, or any vehicle), agricultural equipment, construction equipment, or aerospace industries may significantly improve fuel efficiency and reduce carbon emissions. The composite may include carbon fibers or glass fibers. The carbon fibers may be stiffer, stronger, and less heavy than the glass fibers, but generally may be more expensive. Carbon fiber reinforced components may be about 20% lighter than aluminum components and about 50% lighter than some steel components. Carbon fiber reinforced composites may have a higher ratio of strength-to-weight or stiffness-to-weight than aluminum and steel.
Currently, composite components are often fabricated by conventional processes, including a high pressure resin transfer molding (RTM). Composite components may also be formed of pre-impregnated fibers (“prepreg”) and may require an oven or autoclave to cure the prepreg. Traditionally, carbon fiber reinforced composite components are not cost competitive compared to metal components for several reasons. First, the high pressure RTM may require relatively expensive equipment, and high pressure to flow a polymer resin to impregnate the fibers and to reduce surface defects (e.g., pin holes or undesired porosity). Notwithstanding high pressure application of the resin, the surface may still have pin holes or surface defects. A surface with such defects may not exhibit the desired surface finish or be cosmetically desirable. Such surface defects may also make painting the composite surface more difficult. Second, the high pressure RTM may also require longer cycle times to fabricate a composite component compared to metal components. For example, production cycle times for carbon fiber parts; including heating, curing, and cooling the composite component, may take about 45 minutes or longer as compared to seconds for steel or aluminum parts. Third, the material cost may be high for the virgin carbon fibers, and the fiber waste from the RTM may also be very high. For example, up to 40% of the original carbon fibers, when a composite component with complicated shape or geometry is fabricated may be wasted. Also, the production yield for RTM parts is relatively low compared to metal parts due to surface defects.
Manufacturers continue to seek low cost alternative materials, low cost tooling, and faster cycle times to reduce the production cost for composite components.